With respect to such an actuating switch as mentioned above, in many countries the outer diameter of the cylindrical portion of the switch is standardized by their own domestic standard or the like for affording convenience in use as well as in manufacturing such switches. Further, there is a case where various values are set for the diameter by the domestic standard. For example, two kinds of values, 30 mm and 25 mm, are set in Japan and a value, 22 mm, is set in Europe, as the standarized outer diameter of the cylindrical portion of an industrial-purpose actuating switch. Thus, in a world-wide sense, there are various kinds of standardized values for the outer diameter of the cylindrical portion of the actuating switches. Accordingly, the inner diameter of a hole previously formed in a panel for mounting an actuating switch has to be set with selected one of various kinds of standardized values. For this, on the part of users, it has been necessary to previously form a hole having a standardized diameter properly selected depending on the area of a panel in which the hole is formed and on which an actuating switch is to be mounted or depending on the number or size or the like of equipment to be mounted on the panel, and then selectively procure an actuating switch which is conformity with the prepared hole. On the part of makers, therefore, it has been necessary to previously manufacture and stock various actuating switches having their cylindrical portions which are different from one another in their outer diameter, resulting in increase in expense in view of providing metal patterns on one hand and troubles in view of stock management.